A multi-disciplinary study of the development of a hereditary cardiomyopathy is presently being carried out, using the 14.6 strain of Syrian hamster. Quantitative electron microscopy of the left ventricle has demonstrated changes in organelles associated with intracellular calcium handling, such as mitochondria and sarcoplasmic reticulum. Age-related changes in the volume fractions and membrane surface areas in the genesis of the myopathy is being studied. Electrophysiology of the myopathy is also to be investigated to determine if action potential parameters associated with the calcium currents are altered. Sub-cellular biochemistry of the myopathic hearts is being studied to determine if the rate of calcium accumulation, as well as the total calcium taken up, by both mitochondria and sarcoplasmic reticulum is affected.